Question 1

What is Null-Einspeisung?

Accepted Answer

Zero-feed-in: the inverter throttles PV output so no surplus is exported to the grid. Only the share you consume on-site counts; excess generation is curtailed.

Question 2

What is a Balkonkraftwerk?

Accepted Answer

A plug-in mini-PV system (in Germany capped at 800 W inverter output) that feeds directly into a household circuit. Registration in the Marktstammdatenregister is required.

Question 3

How is the annual consumption simulated?

Accepted Answer

An 8,760-hour (one full year) simulation. Hourly load is derived from the BDEW H25 standard load profile for households and scaled to the kWh value you enter.

Question 4

What does Autarky mean?

Accepted Answer

The share of your total electricity demand that is covered directly by your PV system — i.e. consumption that does not require grid import.

Question 5

What is the Self-consumption rate?

Accepted Answer

The share of the PV electricity you generate that is used on-site (rather than curtailed under Null-Einspeisung or exported).

Question 6

How is EV consumption calculated?

Accepted Answer

Annual km × kWh per 100 km ÷ 100. This value is added to your household consumption to form the total annual demand used in the simulation.

Question 7

Why is there no feed-in revenue?

Accepted Answer

With Null-Einspeisung enabled, surplus PV is curtailed instead of exported — so there is no kWh delivered to the grid and no feed-in tariff to credit.

Question 8

How accurate is the simulation?

Accepted Answer

It is an estimate based on standard load profiles and an average yield of roughly 1,000 kWh/kWp per year. Real results depend on location, roof orientation, shading, weather and individual consumption behaviour.

FAQ / Technical glossary